its just one wire, my 1970 chevy with SB 350 was switched to HEI before i bought it and i looked at all of it cause i'm redoing the whole truck. but i had to redo it cause i cut the wire and don't know what i did with it so i found witch wire connected to the key for the ignition, gotta pull the plug of the key part and one says IGN so i just spliced the wire hooked my HEI wire on and ran it through one of the openings in the firewall now its been a little while since i looked at it bout 2-3 weeks but thats what i remember i'll have a look at it and let ya know if anything is incorrect
